We performed to evaluate the safety of GMOs for a long term exposure in Sprague-Dawley (SD) rats. In this study, groups often or fifteen SD rats were fed one of the following four diets for 90 days: (1) AIN-76A rodent diet only; (2) AIN-76A rodent diet containing 5% genetically modified soybean from USA; (3) AIN-76A rodent diet containing 5% genetically non-modified soybean from USA; (4) AIN-76A rodent diet containing 5% genetically non-modified soybean from Korea. The effects of AIN-76A rodent diet containing genetically modified soybean on body weights, food uptake, water consumption, hematology, serum bio-chemistry, urinalysis, organ weights, gross findings and histopathological findings were not significantly different, compared with others. Taken together, these results suggested that genetically modified soybean did not induce any toxic effects in rats treated for 90 days.